122k views
1 vote
Point B is the center of the circle shown, and the length of arc AC is 8π. What is the area of the circle?

Point B is the center of the circle shown, and the length of arc AC is 8π. What is-example-1

2 Answers

0 votes

Answer:

A

Explanation:

User Ian Jacobs
by
8.2k points
3 votes

Answer:


A=324\pi \text{ units}^2\approx1017.88\text{ units}^2

Explanation:

The formula for arc length is:


\stackrel{\frown}{A}=2\pi r((\theta)/(360)})

Where Θ is measured in degrees.

We know that the arc length is 8π when the degree is 80. So, substitute 8π for A and 80 for Θ:


8\pi=2\pi r((80)/(360))

Divide both sides by 2π:


4=r(80)/(360)

Simplify the fraction:


4=(2)/(9)r

Multiply both sides by 9/2:


r=18

So, the radius is 18.

Now, we can find the area of the circle. The formula for the area of a circle is:


A=\pi r^2

Substitute 18 into r:


A=\pi (18)^2

Simplify:


A=324\pi \text{ units}^2\approx1017.88\text{ units}^2

And we're done!

User Drew Hunter
by
7.8k points
Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories